Lock cylinder unit



Feb. 3, 1970 5.1.. SCHLAGE 3,492,842

LOCK CYLINDER UNIT Filed Aug. 25, 1967 4 Sheets-Sheet 2 73 FIG.

INVENTOR.

ERNEST L. SCHLAGE BY A TORNEVS Feb; 3, 1970 E. L. SCHLAGE 3,492,342

LOCK CYLINDER UNIT Filed Aug. 25, 1967 4 Sheets-Sheet 3 INVEN TOR.

ERNEST L. SCHLAGE BY ATTORNEYS Feb. 3, 1970 IE. L. SCHLAGE 3,492,342

LOCK CYLINDER UNIT Filed Aug. 25, 1967 4 Sheets-Shet 4 INVENTOR. ERNEST L. SCHLAGE ATTORNEVS United States Patent 3,492,842 LOCK CYLINDER UNIT Ernest L. Schlage, Burlingame, Ca]if., assignor to Schlage Lock Company, a corporation Filed Aug. 25, 1967, Ser. No. 663,297 Int. Cl. Eb 27/00 US. Cl. 70369 Claims ABSTRACT OF THE DISCLOSURE A lock cylinder unit of the pin tumbler type has a circular cylindrical plug containing the keyway and comprised of several parts, one part being axially removable by use of an appropriate key so that by insertion of a replacement plug part the response of the lock cylinder unit to different keys can be changed.

My invention relates primarily to builders lock units and especially to the cylinder portion of a lock unit having a pin tumbler mechanism. By use of an appropriate key, the lock cylinder unit can be changed from locked condition to unlocked condition and by use of a special key the response of the lock unit to different keys can be easily changed. A somewhat related device is disclosed in my copending application entitled Pick Resistant Lock Unit filed June 19, 1967 with Ser. No. 647,103.

In the use of pin tumbler, cylindrical lock units, there often arises a necessity for altering or changing the lock unit in an authorized fashion to accept and reject certain keys.

This change can be made by removal of the lock cylinder unit and alteration of the pin tumbler mechanism by a locksmith. This involves disassembly of the mechanism, the services of a skilled artisan, and a substantial amount of time.

It is therefore an object of my invention to provide a lock cylinder unit which can readily be changed by an unskilled but authorized person with an appropriate key.

Another object of the invention is to provide a lock cylinder unit in which a change mechanism can be embodied but without radical alteration in the envelope con figuration or general arrangement of the lock unit itself.

Another object of the invention is to provide a lock cylinder unit in which key acceptance can be changed from the accessible portion of the lock unit without requiring any elaborate disassembly and reassembly of the mechanism.

Another object of the invention is to provide a lock cylinder unit which can readily be incorporated with lock units of the type already available and which can be made on present production machinery.

A still further object of the invention is in general to provide an improved lock cylinder unit.

Other objects, together with the foregoing, are attained in the embodiment of the lock cylinder unit described in the accompanying description and illustrated in the accompanying drawings, in which:

FIGURE 1 is a fragmentary view of a portion of a door panel showing a lock cylinder unit of the invention mounted thereon in its normal position;

FIGURE 2 is a cross-section through the lock cylinder unit illustrated in FIGURE 1, a portion of the mechanism being broken away to reduce the size of the figure and to disclose the interior construction;

FIGURE 3 is a cross-section, the plane of which is in dicated by the line 33 of FIGURE 2, with the cylinder plug rotated about 30 clockwise from the FIGURE 2 position;

FIGURE 4 is an isometric view of a lock cylinder from 3,492,842 Patented Feb. 3, 1970 which a portion has been broken away to disclose the interior construction;

FIGURE 5 is an isometric view of a plug frame disposed on the same axis as the lock cylinder;

FIGURE 6 is a perspective view of a plug block arranged on the same axis as FIGURES 4 and 5 so that FIGURES 4, 5 and 6 when considered together constitute an exploded view;

FIGURE 7 is a view comparable to FIGURE 2 but disclosing a modified form of construction pursuant to the invention;

FIGURE 8 is a cross-section, the plane of which is indicated by the line 8-8 of FIGURE 7;

FIGURE 9 is an isometric view of a plug block portion;

FIGURE 10 is an isometric view on the same axis as FIGURE 9 showing a modified form of plug frame;

FIGURE 11 is an isometric view on the same axis as FIGURES 9 and 10 showing another portion of a plug block, FIGURES 9, 10 and 11 when considered together constituting an exploded view;

FIGURE 12 is a view comparable to FIGURE 2 but showing a further modified form of lock cylinder unit;

FIGURE 13 is a cross-section the plane of which is indicated by the line 1313 of FIGURE 12 with the plug rotated in one direction from the FIGURE 12 position;

FIGURE 14 is a view similar to FIGURE 13 but with the plug rotated 90 in the other direction from the position shown in FIGURE 12;

FIGURE 15 is an isometric view showing a lock cylinder with a cylinder plug frame in a rotated position therein and without a plug lock being present;

FIGURE 16 is an isometric view on the same axis as FIGURE 15 disclosing a plug block, FIGURES 15 and 16 when considered together constituting an exploded view;

FIGURE 17 is an isometric view of a plug frame of a modified form;

FIGURE 18 is a perspective view on the same axis as FIGURE 17, showing a modified form of a plug block, FIGURES 17 and 18 when considered together constituting an exploded view;

FIGURE, 19 is an end elevation of a modified form of plug pursuant to the invention;

FIGURE 20 is an end elevation of a further modified form of plug pursuant to the invention;

FIGURE 21 is an isometric view of a form of key usable in the keyways of the various forms of lock cylinder unit disclosed, except FIGURE 20;

FIGURE 22 is an isometric view of a key comparable to the key of FIGURE 21 but with a modified form of key bow; and

FIGURE 23 is a cross-section to an enlarged scale of the key of FIGURE 21, the plane of section being indicated by the line 2323 of FIGURE 21.

In its usual environment my lock cylinder unit is utilized with a lock unit of recognized configuration. Customarily this is a cylindrical lock mounted on a hinged door panel 6 having an end face 7. Mounted on the end face is a face plate 8 through which project a latch bolt 9 and a deadlatching plunger 11. These mechanisms are parts of a cylindrical or tubular lock unit 12 including an escutcheon 13 abutting the door panel 6 and also including a knob 14 rotatable about a central axis. Operation of the knob 14 eifectuates operation of the latch bolt 9 and of the deadlatching plunger 11 in the regular fashion.

The actuation of the latch bolt 9 by the knob 14 is effectuated in the usual way by a driver bar 16 (FIGURE 2) incoroprated with a lock cylinder 17 disposed inside the knob 14. The driver bar 16 extends generally along the axis of rotation of the knob. An enlarged head 19 on the driver bar is confined within one end of a cylinder plug 21 having a generally circular cylindrical exterior envelope concentric with the axis 18 and rotatable within a. plug bore 22 within the lock cylinder 17. The plug 21 is confined against axial displacement in one direction by a flange 23 abutting one end of the lock cylinder and is confined in the other direction against axial movement by a cap 24 threaded upon and held in position at the end of the plug 21. The cap likewise confines the head 19 of the driver bar. The plug 21 and the driver bar are held against rotation with respect to each other and since the plug 21 is rotatable within the cylinder 17 the driver bar 16 is similarly rotatable relative thereto.

In accordance with this embodiment of the invention the plug 21 is not made of a single piece of material as is customary. Rather, the plug 21 is comprised of a number of different pieces. In this instance the plug 21 is made up of a plug frame 26 generally circular cylindrical in its envelope contour except that it is provided with an axially extending, stepped channel 27 in which a plug block 28 is axially movable. The plug block when in position completes the circular cylindrical envelope of the plug frame so that when considered together the frame and plug amount to a complete, rotatable plug. Since the channel 27 is stepped, the plug block is confined in a radial direction and can move only axially.

The plug block and the plug frame together define a keyway 29 extending axially and partly or entirely through the plug 21, the keyway being narrower than the channel 27. As disclosed in my above-identified copending application, the keyway 29 preferably has the shape of an inverted letter T. Reference to inverted is only for convenience in description since the entire lock cylinder unit can be installed in various different orientations and the keyway changes position as the plug 21 is rotated. As normally installed and seen, however, and as illustrated in FIGURE 1, the keyway is similar to an inverted T in cross-section.

Merging with or intersecting the keyway 29 are various tumbler bores 31, all arranged in a single plane intersecting the axis 18 and extending parallel to each other through the plug frame 26. The tumbler bores 31 are generally circular cylindrical and each of them is provided with a. slidable tumbler pin 32. There can be additional tumbler pins in each of the bores 31 to provide for master keying, but for simplicity herein but a single tumbler pin is shown in each of the tumbler bores, although the length of the various tumbler pins may vary from position to position.

Designed to align with the tumbler bores 31 in one rotated position of the plug 21 within the cylinder 17 are pin bores 33 of circular cylindrical configuration and aligned in a parallel coplanar fashion. Each of the pin bores is provided with a driver pin 34 freely movable therein and adapted to abut the subjacent tumbler pin 32 under the urgency of a spring 36 confined between the end of the pin bore 33 and the end of the pin 34 therein. The various driver pins may be of different lengths. When the various driver pins and tumbler pins are appropriately positioned by a proper key their meeting faces or shearing faces are all substantially coincident with the circular cylindrical envelope contour of the plug 21 and the plug can be rotated. Otherwise rotation is prevented by one or more of the pins straddling the shear line.

Adapted to enter the keyway 29 by an axial sliding movement is the bit 41 of a key 42 having an operating bow 43 for manual gripping. The key bit 41 not only has a transversely extending portion 44 but likewise has an upright portion 46, the latter having edge serrations 47 designed to cooperate with the varying tumbler pins 32. When the key bit is fully insertedin the keyway, as shown in FIGURE 2, the pins .are all arranged with their shear surfaces properly located so that the key 42, the plug 21 and the driver bar 16 rotate concurrently about the axis 18 to actuate the lock mechanism.

Particularly pursuant to the present invention the plug block 28 is provided with a radially disposed pin 51 positioned in the plug block and extending into a circumferential groove 52 cut into the material of the lock cylinder 17, preferably between the outermost and the adjacent pin bores 33. The pin 51 operates freely in the groove, keeps the plug block in position for free rotation and restrains the plug block against axial movement except in two rotates positions. Merging with or intersecting the circumferential groove 52 are axially extending grooves 53 and 54 opening to the end face of the cylinder 17 Although but one groove is necessary, two are provided in symmetrical positions with respect to the plane of the various pins 32 and 34. Disassembly of the plug block can take place either by a clockwise rotation or a counterclcokwise rotation and axial withdrawal with the pin 51 sliding in either the groove 53 or 54. For example, if a change key (not shown) having a full length, continuous, recessed lower surface on the transverse portion 44 is introduced into the keyway 29 and is then rotated approximately 30 in either direction, the pin 51 aligns with either the groove 53 or the groove 54. The rotation of the plug 21 as a whole has moved the tumbler pins 32 out of registry with the driver pins 34. The various pins are all radially confined by the bore wall and plug surface. Thus, this rotation can only be effectuated if an authorized or proper change key has been used.

The plug block 28 can be axially withdrawn quite easily by gripping the exposed portion of the block and sliding the block along the unobstructed under surface of the change key. The start of this motion can be assisted by the insertion of a sharp blade between the flange of the block 28 and the end of the cylinder unit 17.

As part of the security attribute of the lock unit, it is preferred that the plug block 28 have on its upper surface defining the keyway one or more axially extending ridges such as 58 and 59 arranged in any desired position with respect to the central plane of the keyway. Correspondingly, all proper keys must have grooves to accept the ridge or ridges, if any.

Following the removal of the plug block with ribs such as ribs 58 and 59, a replacement plug block can be introduced. The replacement block may have but a single one of the ribs such as 58 or 59, for example, or can have any other desired arrangement of ribs. After the replacement plug block has been axially introduced by sliding along the unobstructed under side of the change key and the whole plug has been rotated back to initial position, the change key can be withdrawn.

Subsequent use of the lock is accomplished by use of a different key having its lower surface grooved or contoured to meet the ribs of the newly installed plug block. In this fashion the contour of the keyway can easily be altered just with the use of a change key and a substitute block. During the change operation the user must hold the change key in a position retaining the tumbler pins 32 in position against gravity. To assist in holding the key in position, if desired, the plug block 28 can be made short. A bit of plug block can remain in the keyway, as shown in FIGURE 2, so that the tip of the key bit has a support at its remote end.

A key 42 for ordinary use and any key that is not to be utilized to change the plug block is especially provided, as shown in FIGURE 2, with a projecting lug 61 thereon. In the actuating position of the key 42 the lug lies against the outer face of the plug block 28. When a key 42 having a lug 61 is used, alignment of the pin 51 with either one of the grooves 53 or 54 in either rotated position is immaterial. The turned plug block can still not be moved axially as the lug 61 on the key 42 obstructs the plug block. The turned key itself cannot be withdrawn because in a rotated plug position the tumbler pins 32 are out of registry with the driver pins 34. The ends of the tumbler pins 32 abut the continuous bore surface of the lock cylinder 17, and cannot be radially displaced by the serrations on the key. Thus, the partly rotated key is held axially in position and the lug 61 retains the plug block 28. Thus, no plug block change is possible when a key 42 with a lug 61 is used. However, an authorized change key, accommodating the ridges 58 and 59, and without a lug 61 always permits plug block changing.

A somewhat comparable arrangement is shown in FIGURES 7 to 11 with all of the parts being similarly operable except that the plug block is in a different environment. In this arrangement the plug 70 includes a plug block 71 considerably shorter than the plug frame 72. The plug block 71 has a peripheral groove 73 in which a special locking ring 74 (FIGURE 8) is disposed. This ring is an interrupted annulus and at one portion has a radially projecting lug 76 designed to slide in either one of two symmetrically placed axial grooves 77 and 78 cut in the cylinder 79. The operation of this portion of the structure is the same as described previously. In addition, the plug block 71 is quite short and the plug 70 is also provided with a secondary captive plug block 80. This has a cross-sectional contour similar to that of the plug block 71 and has a retaining ring 81 similar to the ring 74 but with a narrower gap. When the plug 70 is turned approximately 57 clockwise (FIGURE 8) so that the plug block 71 lies between the spaced ends of the ring 74, the plug block 71 can be axially withdrawn if a key without a lug is employed. Because the gap in the ring 81 is too narrow, the secondary plug block 80 cannot be moved axially toward the plug block 71 although the secondary plug block can be removed axially in the other direction by unscrewing the end cap 86.

Preferably the secondary plug block 80 has an axial bore 82 in which a spring 83 is lodged. A plunger 85 is pressed by the spring against the plug block 71. When an appropriate key is introduced into the keyway and is properly turned, the spring thrust dislodges the plug block 71, as shown in dotted lines, so that the plug block can be readily removed. When installing a substitute plug block, the user depresses the new plug block to displace the plunger 85 toward the left in FIGURE 7. With this mechanism also and by the use of appropriate keys the configuration of the keyway can readily be changed.

In all the structures shown in FIGURES 1 to 11, the bottom portion of the composite plug has been the portion removable and replaceable. In FIGURES 12-16 inclusive, it is the upper portion of the composite plug which is removable. Some or all of the tumbler pins are likewise removed therewith. A cylinder 101 (FIG- URE 12) has a rotatable plug 102 therein substantially as before, the plug including a plug frame 103 and a plug block 104. The plug block in this instance is formed with the tumbler bores 106 in which tumbler pins 107 are disposed. A key 108 operates in the composite keyway 109 as before. The plug block 104 is provided with an offset, projecting pin 111 designed to turn freely within a circumferential groove 112 within the cylinder 101 and to be axially movable with respect to the cylinder but only when in either of two opposite positions. In those positions the pin 111 registers with either of a pair of axially extending grooves 113 and 114 leading to the end face of the cylinder 101.

In addition, there is provided a special addition included in the holding and releasing mechanism. In the plug block 104 there is provided a movable pin 116 of enlarged central diameter urged by a coil spring 117 toward a retracted position with the outermost end of the pin 116 out of the groove 112. A normal key 108 cams against the opposite, inner end of the pin 116 compressing the spring 117 slightly and forcing the outermost end of the pin into the groove 112. The pins 116 and 111 cannot both register with the grooves 113 and 114 at the same time so the plug block cannot be withdrawn.

When a special key 119, as shown in FIGURE 14, is introduced, then the spring 117 again displaces the pin 116 to withdraw the radially outer end thereof from the groove since the inner end of the pin moves into a special depression 121 in the upper face 118 of the key 119. Since the pin 116 is withdrawn from the retaining groove, when the plug 102 is rotated to a proper position either to the left as shown in FIGURE 13 or 90 to the right as shown in FIGURE 14, the key 119 and the plug block 104 together with the various tumbler pins 107 can be withdrawn as a unit. The solid surface of the rotated plug frame underlies the various driver pins 122 holding them in appropriate position. Another plug block perhaps with tumbler pins 107 of different lengths or differently arranged for a different key 108 is introduced into the cylinder 101. Different keys are then effective for operating the plug but a different key not having a depression 121 therein cannot be utilized to change the block 104.

As a further modification, the arrangement of FIG- URES 17 and 18 can be utilized. This is similar to the arrangement of FIGURES 12-16 except that in this instance the plug when assembled (not shown) includes in assembled relationship a plug frame 132 as shown in FIGURE 17 and a plug block 133 as shown in FIGURE 18. With the structures shown the lower configuration of the keyway and the tumbler pins can either or both be changed. Stated differently, only the lower portion of the plug is removable in the construction of FIGURES 1-11, only the upper portion of the plug is removable in the construction of FIGURES 12-16 inclusive, and both upper and lower portions are removable as a unit in the embodiment of FIGURES 17 and 18. The retaining pins 134 and 136 are the same as the pins 111 and 116 as shown in FIGURES 13 and 14. The keyway 137 extends through the plug block 133 and also through the plug frame 132 in the illustrated case. If a somewhat shorter key is utilized, the keyway 137 need extend only through the plug block. It is then not necessary to broach or otherwise pierce the plug frame 132 for a keyway.

In FIGURE 19 there is disclosed a variation on the arrangement of FIGURES 1-11. Instead of having the plug block with a pair of parallel planar sides, the plug frame 141 is supplemented by a plug block 142 which meets with the frame on a generally planar surface 143 of a chordal configuration also defining the lower portion of the keyway 144.

In FIGURE 20 a modification is shown in which the keyway instead of being made up of a pair of rectangular envelopes forming an inverted T has a rectangular upright portion 146 with an arcuate transverse portion 147. As another variation, the upper portion of the keyway has ridges 148 and 149 instead of the bottom portion of the keyway having ridges upstanding therefrom as shown in FIGURES 3 and 19.

As appropriate keys for the various lock cylinder units, there can be provided devices as shown in FIGURE 21 in which the transverse portion 151 of the key shank is continued in the same plane to form a fiat key bow 152 with serrations 153 and an appropriate stop 154 upstanding from the upper surface of the key bit. The stop 154 can be omitted if stop shoulders 156 and 157 are provided at the meeting portions of the bow with the bit. Although it is necessary to utilize only one of the stops, it is preferred to use several. The shank 151 is provided with appropriate grooves 158 to cooperate with the various ridges in the plug.

In FIGURE 22 the key of FIGURE 2 is further illustrated and indicates that with an upright how 43 a stop 161 is utilized in place of shoulders like the shoulders 156 and 157.

Any of the keys can have a cross section like that shown in FIGURE 23 in which the bottom surface or the top surface or both are provided on opposite sides of the center with one or more of a plurality of grooves 158. In the instance shown the grooves are six in number but are capable of being used in various combinations from a single groove in any one of the six positions up to all six grooves being utilized.

What is claimed is:

1. A lock cylinder unit comprising a lock cylinder, means defining a plug bore in said lock cylinder extending along an axis, means defining driver pin bores in said lock cylinder intersecting said plug bore, driver pins in said driver pin bores movable toward and away from said plug bore, a plug rotatable in said plug bore, said plug including a plug frame and a plug block movable axially relative to each other, means defining an axially extending keyway in said plug, means defining tumbler bores in said plug intersecting said keyway and registering with said driver pin bores in one position of said plug in said plug bore, tumbler pins in said tumbler bores movable toward and away from said keyway, means for holding said plug frame against axial movement relative to said lock cylinder, and means effective in one rotated position of said plug for holding said plug block against axial removal from said lock cylinder and eflective in another rotated position of said plug for releasing said plug block for axial removal from said lock cylinder.

2. A look cylinder unit as in claim 1 in which said other selected position is with said driver pin bores and said tumbler pin bores rotated out of alignment.

3. A lock cylinder unit as in claim 1 in which said plug block releasing means includes a key adapted to be received in said keyway.

4. A lock cylinder unit as in claim 1 in which said plug block holding and releasing means is adapted to cooperate with either of two keys each having a bow and each of which is adapted to be received in said keyway, one of said keys including means for retaining said plug block against axial removal from said plug frame and the other of said keys being adapted to permit axial removal of said plug block from said plug frame.

5. A lock cylinder unit as in claim 1 in which said plug frame and said plug block when assembled are in axially overlapped relationship and are substantially circular cylindrical in external contour.

6. A lock cylinder unit as in claim 1 in which said plug block holding and releasing means includes means defining a circumferential groove and an intersecting axial groove extending to one end of said locking cylinder and includes a projection movable within said grooves.

7. A lock cylinder unit as in claim 4 in which said retaining means on said one key is a lug in the path of axial movement of said plug block toward said bow.

8. A lock cylinder as in claim 1 in which one portion of said keyway is partially defined by said plug frame and the axially opposite portion of said keyway is partially defined by said plug block.

9. A lock cylinder unit as in claim 1 in which said plug block holding and releasing means includes a pin movable between a holding position with said pin substantially out of said keyway and a releasing position with said pin extending substantially into said keyway, and a spring for urging said pin toward said releasing position.

10. A lock cylinder unit as in claim 1 including spring means for urging said plug frame and said plug block axially apart.

References Cited UNITED STATES PATENTS 234,630 11/1880 TOWne 70375 587,564 8/1897 Voight 70-34O 1,463,495 I 7/1923 Borelli 70-358 1,917,778 7/1933 Smith 70-388 MARVIN A. CHAMPION, Primary Examiner R. L. WOLFE, Assistant Examiner US. 01. X.R. 70-375, 385, 401, s 

